The present invention is in the field of conveyor belts for pipe conveyors. More specifically this invention relates to the type of pipe conveyor belts wherein the edges overlap when the belt pipe is formed.
With tube conveyors, also referred to as hose-type belt conveyors, or pipe conveyors, mechanical means are used to form the conveyor into a closed tube in the conveying zone. The conveying zone is the area downstream of the loading area, and upstream of the discharge area. Difficulties arise in use for these types of conveyors in regards to controlling the rotation of the belt. Prior art has steel cords or other reinforcements running throughout the belt. Therefore, the overlap section is heavier than the rest of the belt, since it has two full reinforced areas on top of each other. This top heavy section causes the belt to rotate as the belt encounters horizontal or vertical curves. Rotation of the belt can cause damage to the belt edges, and also can cause leakage of the conveyed material. Further, these cords can cause the belt to buckle as the belt encounters horizontal or vertical curves. The cords are useful in the overlap region however, as when rotation does occur, they help maintain a seal on the belt, such that the material being conveyed is better maintained within the pipe belt.
A tubular conveyor belt is desired which would maintain a good seal if rotation occurs, and which would better resist rotation. Further, a tubular conveyor belt is desired which would resist buckling during horizontal or vertical curves.